Nitrox question

[jextract]

My LDS (Hollywooddivers in L.A.) blends Nitrox before filling the cylinders and he told me that because of that my cylinder will not be O2-clean. If I continue to have him fill my cylinder, does it matter? What if I go to another shop that fills partials? Also, my Atomic regulator manual says I can't go back and forth between nitrox and air. What happens if I do? Will my lungs spontaneously combust? HELP! Thanks!

 

[padiscubapro]

My LDS (Hollywooddivers in L.A.) blends Nitrox before filling the cylinders and he told me that because of that my cylinder will not be O2-clean. If I continue to have him fill my cylinder, does it matter? What if I go to another shop that fills partials? Also, my Atomic regulator manual says I can't go back and forth between nitrox and air. What happens if I do? Will my lungs spontaneously combust? HELP! Thanks!

Atomic is VERY clear about their nitrox policies.. All their regs are to be dedicated to either Air or Nitrox service.. and the Nitrox gas is to be hydrocarbon free..
If they are the brass or monel regs they are somewhat forgiving.. if its the titanium reg under no circumstances shoud you use it with nitrox after it has been contminated by hydrocarbons. if the nitrox source has hydrocarbons which is what the LDS is implying, I'd get gas elsewhere...

if he has a clean system and blends by partial pressure to his banks, his gas should be clean and wouldnt effect your tanks.. many LDS use membrane systems without the proper filtration and can put contaminated gas into the system.

 

[bburns24]

Removed

 

[SDAnderson]

My LDS (Hollywooddivers in L.A.) blends Nitrox before filling the cylinders and he told me that because of that my cylinder will not be O2-clean.

Take him at his word for it - he isn't pumping hyperfiltered air in his nitrox and your tanks will no longer be O2 clean.

If I continue to have him fill my cylinder, does it matter?

As long as you don't use anything higher than EAN 40, are getting all your fills from banked EAN and never partial pressure blend, it shouldn't matter.

What if I go to another shop that fills partials?

Your tanks won't be O2 clean and you may cause a very big explosion.

Also, my Atomic regulator manual says I can't go back and forth between nitrox and air. What happens if I do? Will my lungs spontaneously combust?

So long as you never use your regulator for higher than EAN40, it shouldn't matter. If you ever intend to use higher than EAN40, you should dedicate a regulator to that gas and never let gas that isn't hyperfiltered pass through it.

 

[Zippsy]

What deepsix probably meant to say in addition to that other helpful quote was "here is a link to some further information: http://69.93.91.170/t18911.html "

 

[jextract]

Atomic is VERY clear about their nitrox policies.. All their regs are to be dedicated to either Air or Nitrox service.. and the Nitrox gas is to be hydrocarbon free..
If they are the brass or monel regs they are somewhat forgiving.. if its the titanium reg under no circumstances shoud you use it with nitrox after it has been contminated by hydrocarbons. if the nitrox source has hydrocarbons which is what the LDS is implying, I'd get gas elsewhere...

if he has a clean system and blends by partial pressure to his banks, his gas should be clean and wouldnt effect your tanks.. many LDS use membrane systems without the proper filtration and can put contaminated gas into the system.

Thanks, PadiScubaPro, for the very informative answer. Hollywoodivers does indeed use a membrane system but I'm a little confused as to why they say it's OK if I continue to use only them to fill. Won't the situation become worse? And as to my regulator issue, is this unique to Atomic? When I got my certification the dive center used the same regs for both air and nitrox interchangeably.

And thanks also to ReefRaff and Zippsy for the help as well, and to bburns. I will indeed talk to the shop about the O2 cleaning issue.

You guys are great and I appreciate your help.

 

[H2Andy]

let's please not make personal comments about each other, even if you feel provoked.

good info so far, keep it coming.

 

[jextract]

My apologies.

 

[d33ps1x]

I apologize too. My comment wasn't intended to be personally directed at you but instead at your Nitrox instructor. The questions you asked above are about key safety components covered in any Nitrox training I've ever heard of.

Personally I have PADI EAN, TDI Nitrox Gas Blender and Advanced Gas Blender and it definately was well covered in the first and most definately in the other two.

I can see where it came off as demeaning to you. I was actually just angry that an instructor could let you walk out of a class that you probably paid pretty good money for, without these concepts understood and ingrained.

Then again I am assuming that you have nitrox training by the questions you are asking. Maybe that was wrong too. Who knows.

My apologies none the less for the unintended slam. The point either way is to help people not to slam them when they ask a question. I've actually stood up for a lot of people on here when they get slammed for asking questions. I'm big enough to admit I didn't practicing what I preach. Lesson learned.

 

[padiscubapro]

Thanks, PadiScubaPro, for the very informative answer. Hollywoodivers does indeed use a membrane system but I'm a little confused as to why they say it's OK if I continue to use only them to fill. Won't the situation become worse? And as to my regulator issue, is this unique to Atomic? When I got my certification the dive center used the same regs for both air and nitrox interchangeably.

And thanks also to ReefRaff and Zippsy for the help as well, and to bburns. I will indeed talk to the shop about the O2 cleaning issue.

You guys are great and I appreciate your help.

contamination is builds over time.. if his gas has hydrocarbons since his oxygen percentage is relative low the risk is lower during filling (note I did not say eliminated) if he deposits hydrocarbons on your tank and valve it becomes dangerous for someone filling your tank by partial pressure blending..

The risk on a brass or monel reg combusting in a low nitrox percentage is minimal (but not zero), more likely is partial combustion which you might never know you had.. what this is is when the reg is pressureized some of the hydrocarbons burn, releasing co2 and co, and in some cases toxic gases if orings or seats combust...

If you purchased the titanium reg, the regs must be ablsolutely clean in the presence of oxygen.. Titanium burns very very easily, about the only metal that burns easier is magnesium..

The best way to reduce the risk is to use dedicate regs and get gas from a source that does things correctly.. a good habit to get into is pressurize the regs S L O W L Y, just crack the valve ever so slightly and allow the gas to come up to pressure, this will keep heat generated by adiabatic compression to a minimum.

I defer to the experts like NASA or the GCA which basically treat anything with more oxygen than AIR is treated as OXYGEN.


The reg policies of Oceanic, Mares, Atomic and I belive scubapro are the same.. dont mix normal air (21% oxygen compatible gas is ok) and Oxygen enriched mixtures. Regs are to be recleaned if exposed to contaminates.. These policies are usually stated in the repair manuals but not always in the owners manuals..